Actively exploited
Listed in CISA’s Known Exploited Vulnerabilities catalog since July 14, 2026.
CVE-2026-56155
Microsoft Active Directory Federation Services Insufficient Granularity of Access Control Vulnerability
Microsoft · Active Directory Federation Services
Published July 21, 2026
What happened
Microsoft Active Directory Federation Services contains an insufficient granularity of access control vulnerability that allows an authorized attacker to elevate privileges locally.
What it means for your business
Microsoft Active Directory Federation Services is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2026-56155). Microsoft Active Directory Federation Services contains an insufficient granularity of access control vulnerability that allows an authorized attacker to elevate privileges locally. CISA remediation due date: 2026-07-28. PremierePC tracks KEV alerts for Upstate SC businesses — patch or open a ticket if you need help verifying exposure.
Required action
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
CISA due date: July 28, 2026
Sources
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